The recipe went something like this:
Whisk the egg, egg yolk and sugar until well mixed.
Squeeze in about half a tube of wasabi paste. Add more or less depending on how spicy you want it. Continue whisking until the wasabi is evenly mixed into the egg and sugar mix.
Whisk in the double cream and then the milk, stirring until the sugar is mostly dissolved.
Transfer the mix to the freezer and crank until frozen.